title: Effects of moderate and chronic exercise on the nitrergic system and behavioral parameters in rats.
abstract: Several reports suggest that nitric oxide (NO) could play a critical role on synaptic plasticity related to physical activity improving learning and memory; thus, physical exercise would have important effects on cerebral health. In order to analyze the long-term effects of chronic moderate physical training on the morphology and activity of nitrergic neurons belonging to the cerebral cortex, hippocampus and striatum, and their relationship with behavioral parameters. Wistar rats were aerobically trained (AT) up to the age of 18months and compared to sedentary controls (SC). At the end of the training protocol behavioral parameters were analyzed in an eight-arms radial maze. Rats were sacrificed by perfusion fixation with 4% paraformaldehyde. Brains were dissected out and coronal sections containing the three mentioned areas were obtained. The neurons expressing nitric oxide synthase (NOS) were stained using the technique of NADPH-diaphorase (NADPH-d) and their morphological and densitometric parameters were quantified by image analysis. Afterwards, the isoforms of NOS were determined by immunofluorescence. Results revealed AT rats learned faster, performed less mistakes and were more successful than SC rats in the maze. The nitrergic neurons of the cerebral cortex were larger and they had an increased number of dendrites. The NADPH-d reactivity in the cortex and striatum was upregulated. Colocalization was significant for the neuronal nitric oxide synthase (nNOS), in both groups. In conclusion, moderate and chronic exercise had a positive effect on cognitive performance and anxiety related behavior. An upregulation of the nitrergic system was detected in AT rats and this fact could be involved in this beneficial action on the aged subjects.
authors.affiliation: School of Health Sciences, Department of Basic Sciences Research, University of Business and Social Sciences (UCES), Bs As, Argentina. apietrelli@uces.edu.ar
authors.forename: Adriana
authors.initials: A
authors.lastname: Pietrelli
authors.forename: Juan José
authors.initials: JJ
authors.lastname: López-Costa
authors.forename: Ricardo
authors.initials: R
authors.lastname: Goñi
authors.forename: Esther María
authors.initials: EM
authors.lastname: López
authors.forename: Alicia
authors.initials: A
authors.lastname: Brusco
authors.forename: Nidia
authors.initials: N
authors.lastname: Basso
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001921:Brain / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D007091:Image Processing, Computer-Assisted; D018782:Maze Learning / Q000502:physiology; D009252:NADPH Dehydrogenase / Q000096:biosynthesis; D026602:Nitrergic Neurons / Q000378:metabolism*; D052248:Nitric Oxide Synthase Type I / Q000096:biosynthesis*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar
chemical_list: D052248:Nitric Oxide Synthase Type I; D009252:NADPH Dehydrogenase